Sexual Dimorphism in Anthropometric Characteristics of Children from Cross River State, Nigeria

Human sexual dimorphism is an outcome of a survival strategy, a balancing of the need for high degree of biological variation within species with the need for a narrow range of variation in the female, who is physically structured for the perinatal support of infant. This study aimed to evaluate sexual dimorphism in anthropometrics of children from the three senatorial zones of Cross River State, Nigeria, viz: southern senatorial zone (SSZ), central senatorial zone (CSZ) and northern senatorial zone (NSZ). The study sample comprised 300 subjects (150 boys and 150 girls) of Cross River State parentage using systematic random sampling and self-administered proforma. The participants were children, age 5 – 11 years. The results showed that length of mandibular arch, hand length and thigh length of girls from SSZ are significantly higher (P <0.05) than that of boys. In contrast, neck length, foot length and ankle breadth of boys in CSZ are significantly higher (P <0.05) in boys compared to that of their female counterparts whereas, for participants from NSZ, bigonial width and neck length were significantly higher in boys than girls. Comparison of anthropometric dimensions based on senatorial zones and sex revealed that girls from SSZ consistently had significantly higher (P <0.05) anthropometric dimensions compared to their counterparts from the other two zones. In conclusion, the findings of this study demonstrate that moderate differences in altitude does not significantly affect average stature or range in variation.

Key Words: anthropometry, stature, Cross River State